Updated Study Results Reinforce Survival Benefit of Docetaxel for Men With Advanced, Hormone-Resistant Prostate Cancer

Docetaxel (Taxotere)-based chemotherapy (with prednisone) maintained long-term efficacy as a treatment for advanced (metastatic) hormone-resistant prostate cancer patients, according to the 3-year updated results of the landmark TAX 327 study. Results of the international multicenter phase III trial were reported in an oral presentation at the 43rd Annual Meeting of the American Society of Clinical Oncology (ASCO).

The TAX 327 data show that among patients with metastatic, hormone-resistant prostate cancer, significantly more of those treated with docetaxel at 75 mg/m

²

combined with prednisone at 5 mg once every 3 weeks survived at least 3 years, compared with those treated with the anticancer antibiotic mitoxantrone combined with prednisone. Patients treated with the docetaxel regimen lived a median of 3 months longer (19.3 vs 16.3 months,

P

= .006) and had a 21% lower risk of dying (hazard ratio [HR] = 17.6–21.3). These results are consistent with results published in 2004 in the New England Journal of Medicine and document the maintenance of the survival benefit previously reported in patients treated with the docetaxel-based therapy.

Survival Benefit Unique

"The results confirm docetaxel's survival benefit in patients with metastatic hormone-resistant prostate cancer," said study author Dominik R. Berthold, department of medical oncology, Princess Margaret Hospital, Toronto. "Prolonged survival is extremely important for these patients, and docetaxel is the only chemotherapeutic agent to demonstrate a survival benefit in this setting."

The TAX 327 study was initiated in 2000 to evaluate long-term survival among men with metastatic hormone refractory prostate cancer treated with regimens of docetaxel plus prednisone (n = 335) or mitoxantrone plus prednisone (n = 337). The primary analysis published in the New England Journal of Medicine in 2004 demonstrated that docetaxel given every 3 weeks with prednisone led to a superior survival advantage, vs mitoxantrone plus prednisone.

The median survival was 18.9 months in the group given docetaxel every 3 weeks and 16.5 months in the mitoxantrone group (HR = 0.76, 95% confidence interval = 0.62–0.94,

P

= .0094). The primary endpoint of the investigation was overall survival. Secondary endpoints measured pain and prostate-specific antigen (PSA) levels.

Adverse Events

The most commonly observed adverse events in the TAX 327 study were alopecia, fatigue, and nausea. Grade 3/4 neutropenia was reported more frequently in the docetaxel group than the mitoxantrone group (32% vs 21.7%, P = .004).

The regimen of docetaxel at 75 mg/m²once every 3 weeks plus prednisone at 5 mg has been approved for use as a treatment for androgen-independent metastatic prostate cancer in the United States since May 2004. It is the only standard-of-care, first-line chemotherapy option for patients with metastatic hormone-refractory prostate cancer.